Method of and devices for conveying, spacing, and timing bevel-walled receptacles



3,382,965 SPACING', AND LES J. PIERCE. JR.. EVICES FOR CONVE ET AL YINGTIMING BEVEL-WALLED RECEP'IAC May 14, 1968 I c.

' METHOD OF AND D Filed Dec. 21, 1966.

10 Sheets-Sheet l INVENTORS. Cbeszer J. Pierce, Jr.

Lawrence J. Pagenoarm l M ATTORNEY May 14, 1968 C. J. PIERCE, JR.. ET3,332,955

METHOD OF AND DEVICES FOR: CONVEYING, SPACING, AND

TIMING BEVEL-WALLED RECEPTACLES Filed Dec. 21, 1966 l0 Sheets-Sheet 2INVENTORS.

Chester 1 Pierce, J'r. Lawrence J Page/Warm M ATTORA/[Y y 14, 1968 c. J.PIERCE, JR. ET AL 3,382,965

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND

TIMING BEVEL-WALLED RECEPTACLES Filed Dec. 21, 1966 10 Sheets-Sheet 3 INVEN TORS Chesfer JFP/erce J).

Fig. 3

BY Lawrence J Pagendarm M ATTORNL'Y May 14, 1968 c, J l c JR" ET AL3,382,965

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND TIMING BEVEL-WALLEDRECEP'IACLES Flled Dec 21 1966 10 Sheets-Sheet 4 v INVENTORS. 'Chesfer ZP/erce, Jr.

Fig. 4

flwrenca J Pagenaarm M ATTORNEY C. J. PIERCE, JR. ET AL METHOD OF ANDDEVICES FOR CONVEYING,

3,382,965 AND May 14, 1963 SPACING TIMING BEVEL-WALLED RECEPTACLES 1OSheets-Sheet Filed Dec. 21, 1966 INVENTORS. Chester J. Pierce, Jli ByLawrence J Pagendarm ATTORNEY May 14, 1968 c. J. PIERCE, JR.. ET3,382,965

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND TIMING BEVEL-WALLEDRECEPTACLES Filed Dec. 21, 1966 10 Sheets-Sheet 6 v INVENTORS. Chesfer 1Pierce, Jr. Lawrence J Pagenaarm f'v-w-M W m ATTORNEY May 14, 1968 c, cJR" ET AL 3,382,965

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND TIMING BEVEL-WALLEDRECEPTAGLES Filed Dec. 21, 1966 10 Sheets-Sheet 7 IN VEN TORS ChesterJ." Pierce, J'r. v Zwrenc'e J pagenaarm v ATTORNEY May 14, 1968 c. J.PRERCE, JR.. ET 3,

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND TIMING BEVEL-WALLEDRECEPTACLES Filed Dec. 21, 1966 10 Sheets-Sheet s I N VEN T 0R5 Chesfer0T P/krce, J72 Lawrence J. Pagendarm M ATTORNEY y 14, 1968 c. J. PlERCE,JR.. ET AL 3,382,9

METHOD OF AND DEVICES FOR CONVEYING, SPACING, AND

, TIMING BEVEL-WALLED RECEPTACLES Filed Dec. 21, 1966 10 Sheets-Sheet 9Fig. 9

INVENTORS. Chesfer J: P/Zrce, Jr.

' Lawrence (Z Pagendarm PM W (L-u; ATTORNEY M y .4, 1968 c. J. PIERCE,1a.. 51' AL 3,382, 65

METHOD OF AND DEVICES. FOR CONVEYING, SPACING. AND

TIMING BEVEIJWALLED RECEPTACLES FiledDec. 21, 1966 10 Sheets-Sheet 10INVENTORS. Che-sler 1 Pierce, Jr; Lpwrence I Pagendarm ATTORNEY UnitedStates Patent 3 382,965 METHOD OF AND DEVICES FOR CONVEY- ING, SPACING,AND TIMING BEVEL-WALLED RECEPTACLES Chester J. Pierce, Jr., Palo Alto,and Lawrence J.

Pagendarm, Redwood City, Calif., assignors to Kliklok Corporation, NewYork, N.Y., a corporation of Delaware Filed Dec. 21, 1966, Ser. No.603,488 7 Claims. (Cl. 198-34) ABSTRACT OF THE DISCLOSURE The presentimprovements deal with the problem of articles with tapered sidesoverriding moving indexing lugs against which the articles are pressedby a conveyor which frictionally engages the articles. The frictionalengagement is progressively reduced as the articles assume tilt withrespect to the supporting surface of the conveyor, for example bytransferring a portion of the article weight to an element which movesno faster than the indexing lug.

In the packaging art, more particularly in the art of packaging foods infolding boxes, it is often necessary to convey receptacles, such astrays, dishes, or pie plates from one station, at which the receptaclesarrive in irregular order, to another station at which each receptacleis inserted by automatic machinery into a folding box. During insertionthe box advances on a box conveyor which supplies the boxes accuratelyspaced in timed sequence.

In order to fill each and every box without failure, it is necessary tosupply the receptacles equally accurately spaced and timed.

For this purpose it is the present practice to convey the receptacles ona transport conveyor on whose surface they rest and onto which they werereleased by a suitable escape mechanism which periodically releases onereceptacle at a time.

As the receptacle is moved along by the conveyor merely by friction andbecause of unavoidable minor variations in the timing of the moment ofrelease, the spacing of the receptacles on the conveyor is onlyapproximate, but not sufiiciently accurate.

It is known, for the purpose of improving the accuracy of spacing andtiming, to intercept the receptacles by lugs of a further conveyor whichmoves at a somewhat slower linear rate than the first conveyor. Thereceptacles run into the aforesaid lugs, whereafter the second conveyorcontrols the rate of advance of the receptacles and also controls theirspacing, which is equal to the spacing of the lugs. As the secondconveyor moves less rapidly than the first, the receptacles thereafterslide on the surface of the first conveyor and the frictional forcebetween receptacle and conveyor surface keeps the receptacle pressedagainst the lug.

Difiiculties are experienced with receptacles comprising tapered wallsagainst which the lug bears. Examples of such receptacles are rimmed orrimless trays or dishes as are used for prepared dinners and pies. Thesereceptacles tend to climb up and override the lugs by reason of thefrictional force acting on them and by reason of the taper of the wallwhich facilitates uptilting and climbing of the receptacles.

For certain reasons the lugs are generally constructed to be retractableor collapsible if acted upon by a force which exceeds a biasing forceapplied to keep the lugs extended. Such structural details arenecessary, for example in order to prevent a lug from upsetting areceptacle on the transport conveyor in the event the lug rises3,382,965 Patented May 14, 1968 into operative position under areceptacle on the transport conveyor. In such a case the lug is allowedto collapse to let the receptacle pass. It then rises behind thereceptacle and intercepts the next one.

If now a receptacle is permitted to climb up on a lug, the lug is alsoin danger of collapsing and, as a result, an undesired receptacle ispassed on to the filling station at which then a jam or misloadingoccurs necessitating shut down of the entire packaging line.

The invention proceeds from the recognition that the cause of climbingof receptacles is the frictional engagement between the receptacles andthe transport conveyor, that uptilting of the receptacles is a dangersignal and that it may be utilized to control or reduce the frictionaladvancing force in such a manner that the force is progressively reducedfor increasing tilt of the receptacle with respect to the level of thetransport conveyor.

This may be accomplished in various ways. One of the simplest ways ofreducing the frictional advancing force is to make the receptaclelighter, so to speak. The basis for this procedure is the fact that theadvancing drive force is proportional to the coefficient of frictionmultiplied by the weight of the receptacle acting on the transportconveyor.

Making the receptacle lighter is most conveniently accomplished bytransferring a portion of its weight onto an element other than thetransport conveyor. This could be a stationary element, such as a rail,but is preferably an element advancing at the same linear rate as thesecond conveyor.

The entire weight reduction step of the method is self controlling. Thegreater the frictional force, the greater the inclination which thereceptacle experiences. The greater the inclination the greater thetransfer of weight (or loss of weight) which, in turn, amounts to acorresponding reduction of the frictional force. Thus the receptacleceases to climb and overriding is prevented.

The objects, features, and advantages of this invention will appear morefully from the detailed description which follows accompanied bydrawings showing, for the purpose of illustration, a preferredembodiment of the invention. The invention also resides in certain newand original features of construction and combination of elements, aswell as steps and combination of steps hereinafter set forth andclaimed.

Although the characteristic features of this invention which are.believed to be novel will be particularly pointed out in the claimsappended hereto, the invention itself, its objects and advantages, andthe manner in which it may be carried out, may be better understood byreferring to the following description .taken in connection with theaccompanying drawings forming a part of it in which:

FIGS. 1 to 5 are perspective views of the progressive advance ofreceptacles on a conveying device incorporating the present invention;

FIG. 6 is a perspective view of a normal engagement of a receptacle withthe intercepting lug of a timing conveyor;

FIG. 7 is a perspective view of an abnormal condition, the receptacleclimbing upon on the lug;

FIG. 8 shows the result of the condition of FIG. 7 as it would occurwithout application of the invention, the receptacle overriding the lugwhich collapsed;

FIG. 9 is a perspective end view illustrating the operation of theweight or friction drive reduction resulting from the invention;

FIG. 10 is an elevational view of an escapement element of the device;and

FIG. 11 is a side view, partially diagrammatic, of a particulardisposition of an article on the conveying mechanism.

In the following description and in the claims various details will beidentified by specific names for convenience. The names, however, areintended to be generic in their application. Corresponding referencecharacters refer to corresponding parts in the several figures of thedrawlngs.

The drawings accompanying, and forming part of, this specificationdisclose certain specific details of construction for the purpose ofexplanation of broader aspects of the invention, but it should beunderstood that structural details may be modified in various respectswithout departure from the principles of the invention and that theinvention may be incorporated in, and its method be practiced by, otherstructural forms than shown.

Referring to FIG. 1, a transport conveyor comprising chains 11 and 12moves articles in a direction towards the observer, the article trackbeing laterally defined by lateral rails 13 and 14. The chains 11 and 12are endless and move at the same linear speed. The upper runs of thechains are substantially horizontal and level and are supported bysupporting rails 15 and 16.

Articles are supplied to the far end of the conveyor by any suitablemeans, for example a roller track which may be slightly downwardlyinclined so that articles placed thereon advance toward the conveyor 11,12 by gravity. The four rollers 17, 18, 19 and 20 at the beginning ofthe conveyor track may be considered a continuation of a roller track.

Articles arrive at the far end of the conveyor and are then released byan approximate escapement or release mechanism for travel on theconveyor chains 11 and 12 which propel the articles merely by reason ofthe frictional contact between the chains and the articles.

The escapement or release mechanism comprises a pair of arms extendingin opposite directions and mounted on a shaft 21. Only one arm isvisible at 22. A finger 23 is pivotally mounted on the arm at 24 and isunder the action of a spring 25 which maintains the finger in anextended position (see also FIG. 10). The finger is deflectable againstthe action of the spring 25 in the event the arm and finger should riseunder an article passing over it. In such a case the finger isdownwardly deflected into a position in which it clears the article, soas not to upset it. The deflected position is shown in broken lines inFIG. 10.

The finger is a periodically operating stop for the articles about toenter onto the conveyor chains 11, 12 and controls, by its downwardwithdrawal, the moment at which articles are released. In the positionin which the stop 22, 23 is shown in FIG. 1 it is about to release afirst tapered dish 26 to which, for convenience of following the articlesequence, a single marker 27 was attached.

In FIG. 2 the first dish is moving toward the observer at the velocity vof the conveyor 11, 12. A second dish bearing a double marker 28 isapproaching the rotating stop 22, 23 to be released thereby at about themoment illustrated in FIG. 3.

In FIG. 2 a centrally disposed conveyor chain 29 is seen to rise intothe path of the articles just ahead of the first dish. The conveyor 29carries uniformly spaced lugs 30 which are tiltably mounted attransverse pivots 31.

Rearwardly of each lug a supporting element 32 is mounted on theconveyor. This element 32 may be considered as being associated with thelug 30 ahead of it, as lug and element cooperate in controlling thelinear rate of advance of an article engaged thereby, as will bedescribed further below.

The lug 30 is two armed, one end 33 being weighted, the other end 34acting as a stop and being lighter than the one end. As a result, thelug is biased to extend into the path of articles moving on the conveyor11, 12 so as to intercept them. The conveyor chain 29 moves at a lowerlinear velocity than the conveyor, consequently the faster movingarticles on conveyor 11, 12 catch up with and abut a lug 30 which thenslows the articles and causes them to advance thereafter at a lowervelocity designated v-Av. In FIG. 3 the first tapered dish is inabutment with, and under the control of, the lug 30. It then continuesto slide on the chains 11, 12 because of the difference in the linearvelocities which is Av.

As shown in FIG. 11, the raised stop end 34 extends above the level ofthe top surface of conveyor chains 11, 12 and is in a position tointercept articles moving on the conveyor 11, 12.

Should by accident a lug 30 rise underneath an article carried on theconveyor 11, 12, the raised end 34 is depressed against the weight biasof the heavy end 33, so that both ends 33 and 34 clear the bottom of thearticle. The degree of clearance is apparent from the broken outline ofthe lug which shows the lug depressed.

FIG. 11 also shows that the supporting element 32 clears the level ofconveyor 11, 12 by an amount h. This amount is so chosen as to providesufficient clearance for the articles on the conveyor, but the top edgeof element 32 is sufliciently close to the level of the supportingsurface of the transport conveyor 11, 12 that articles which assume atilted position on the conveyor 11, 12 (by reason of their tendency toclimb up on the respective raised lug 30, come to rest with theirtrailing portions on the element 32, whereby a portion of the articleweight is transferred onto the conveyor 29. This action, as previouslystated, reduces the frictional drive exerted by the conveyor 11, 12 onthe article and checks further climbing.

Turning to FIG. 6, a bevel-walled dish is shown in a normal position inwhich its beveled front bears against the stop end 34 of the lug 30.

Occasionally it happens that the frictionally imparted driving forceexerted by the conveyor 11, 12 on the dish is so great as to cause thedish to climb up on the lug, which action is aided by the taper of thearticle wall. This condition is illustrated in FIG. 7 and brieflythereafter would lead to overriding of the lug by the dish, as is shownin FIG. 8, were it not for the combination of the lug 30 with anassociated supporting element 32.

FIG. 9 is a view down the conveyor track at about the level of theconveyor 11, 12. It is apparent that the trailing portion of the dishhas dipped low enough to seat on the supporting element 32 which has aforked upper end in order to support the dish at two laterally spacedpoints. It is also seen that the left portion of the dish was liftedcompletely off the chain 12 at 38. The dish now rests with its trailingportion on the supporting element 32 which moves at the rate v-Av. Theright portion of the dish is still engaged by the chain 11, but itsdrive is insufficient to force the dish further up the stop into anoverriding position.

Ideally the dish should be lifted 011 both chains 11 and 12, so as to besupported only by the lug 30 at its leading portion and by thesupporting element 32 at its trailing portions. However, imbalance ofthe dish contents usually results in a slight lateral slant as shown inFIG. 9.

Returning now to the illustrations of the travel of the articles alongthe conveyor track, FIG. 3 shows the first dish 26 in engagement withportion 34 of the lug 30 at a moment when the associated supportingelement (hidden by the dish) is coming up from below on the risingportion of the chain 29. If the supporting element 32 finds the dishsubstantially level, not tending to climb up on the lug portion 34, itwill clear the bottom of the dish. If, however, the dish is slanted sothat its trailing bottom portion dips sufficiently far below the levelof the conveyor 11, 12, the supporting element 32 will raise thetrailing dish portion to reduce its frictional engagement with theconveyor 11, 12, the degree of lift depending on the degree of tilt ofthe dish (see also FIG. 11).

FIG. 4 shows the first dish moving out of the picture. The second dishis approaching a lug 30 which is rising ahead of it. A third dishapproaches the escape mechanism.

FIG. 5 shows the first and second dishes, accurately spaced and timed,entering pockets of a table top-type conveyor 36 fitted with transverselugs 37. This conveyor carries the dishes to a station at which thedishes are inserted into cartons.

A third dish has arrived from the right. A space was left vacant betweenthe second and the third dish in order to show the end of the conveyorchain 29.

What is claimed is:

1. In the method of spacing and conveying articles having a taperedfront, which method comprises the steps of frictionally conveying thearticles at a certain linear velocity on the supporting surface of atransport conveyor and intercepting the articles by spaced lugs of atiming conveyor moving at a linear velocity lower than said certainvelocity to retard the articles and maintain them at a spacing equal tothe lug spacing, the step of progressively reducing the frictionalengagement between said transport conveyor and an article as therespective article assumes an increasingly greater inclination withrespect to the surface of said transport conveyor incidental to itstendency to climb up on a lug with its tapered front.

2. In the method of spacing and conveying circular trays comprising aperipherally tapered wall, such as pie plates, which method comprisesthe steps of frictionally conveying on the supporting surface of atransport conveyor the trays at a certain linear velocity, andintercepting the trays by spaced lugs of a timing conveyor moving at alinear velocity lower than said certain velocity to retard the articlesand maintain them at a spacing equal to the lug spacing, the step ofrelieving a portion of the weight of the respective tray bearing on saidtransport conveyor, in proportion to the inclination of saidrespective'tray with respect to the said supporting surface incidentalto its tending to climb up on a lug with its tapered wall.

3. The method according to claim 2 in which the weight is relieved by atransfer of a portion thereof into the timing conveyor.

4. In a device for conveying and spacing articles, such as trays ordishes having a tapered front, the device comprising, a pair of firstconveyors laterally spaced and driven at the same certain linear rate,said first conveyors comprising a top surface for frictionallysupporting articles thereon, and a timing conveyor comprising aplurality of spaced lugs extending between the first pair of conveyorsand driven at a lower linear rate to intercept said articles byengagement of said lugs with the tapered front of the respectivearticle, said article tending to climb up on, and override, therespective lug, the improvement which comprises a supporting element onsaid timing conveyor rearwardly of a lug with which the element isassociated, said element being at a level sufiiciently far below thesaid top surface to clear level articles moving on said first conveyor,but sufiiciently close to said level to engage the trailing portion ofan article dipping with its trailing portion below said level incidentalto the tilting of the article as it climbs up on the associated lug.

5. A device according to claim 4 in which the lugs are pivotallysupported on said timing conveyor with freedom to tilt about ahorizontal axis from a raised position in which the lugs interceptarticles resting on said first conveyors to a lowered position in whichthe lugs clear said articles on said first conveyor, and in which meansare provided for biasing said lugs towards a raised position within thatportion of the timing conveyor in which its lugs move between thearticle carrying top surfaces of the first conveyors.

6. A device according to claim 4 in which said element has a forkedupper article-supporting portion for engaging the article at twolaterally spaced points.

7. A device according to claim 4 in which the timing conveyor comprisesa rising portion within the zone of engagement by the articles with itslugs so as to cause the said supporting element to raise the trailingportion of an article climbing up on the associated lug.

References Cited UNITED STATES PATENTS 3,263,794 8/1966 Burton 19834RICHARD E. AEGERTER, Primary Examiner.

